{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,15]],"date-time":"2026-04-15T02:29:56Z","timestamp":1776220196772,"version":"3.50.1"},"reference-count":50,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2022,3,14]],"date-time":"2022-03-14T00:00:00Z","timestamp":1647216000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Post-Wildfire work unit of the US Army Corps of Engineers Flood and Coastal Storm Damage Research and Development program","award":["NA"],"award-info":[{"award-number":["NA"]}]},{"name":"USACE Planning Assistance to States program through the Los Angeles District","award":["NA"],"award-info":[{"award-number":["NA"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Geosciences"],"abstract":"<jats:p>The Santa Barbara post-wildfire debris flows and the Brumadinho tailing-dam failure were two of the most catastrophic flood events of the late 2010s. Both these events carried so much solid-phase material, that classic, clear-water, flood risk approaches cannot replicate them, or forecast other events like them. This case study applied the new non-Newtonian features in HEC-RAS 6.1 to these two events, testing the most widely used flood risk model on the two most common mud and debris flow hazards (post-wildfire floods and mine tailing dam failures). HEC-RAS reproduced the inundation boundaries and the event timing (where available) for both events. The ratio between the largest debris flow clasts and the channel size, parametric trade-offs, the \u201cconvex\u201d alluvial plain topography, and the stochasticity introduced by urban infrastructure made the Santa Barbara modeling more difficult and less precise than Brumadinho. Despite these challenges, the results provide prototype scale validation and verification of these new tools in this widely applied flood risk model.<\/jats:p>","DOI":"10.3390\/geosciences12030134","type":"journal-article","created":{"date-parts":[[2022,3,15]],"date-time":"2022-03-15T03:06:10Z","timestamp":1647313570000},"page":"134","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Prototype Scale Evaluation of Non-Newtonian Algorithms in HEC-RAS: Mud and Debris Flow Case Studies of Santa Barbara and Brumadinho"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-2125-3424","authenticated-orcid":false,"given":"Stanford","family":"Gibson","sequence":"first","affiliation":[{"name":"Hydrologic Engineering Center, Davis, CA 95616, USA"}]},{"given":"Leonardo Zandonadi","family":"Moura","sequence":"additional","affiliation":[{"name":"Department of Civil and Environmental Engineering, Universidade de Bras\u00edlia, Brasilia 70910-900, Brazil"},{"name":"CERIS, Instituto Superior T\u00e9cnico, Universidade de Lisboa, Av. Rovisco Pais 1, 1049-001 Lisbon, Portugal"}]},{"given":"Cameron","family":"Ackerman","sequence":"additional","affiliation":[{"name":"Hydrologic Engineering Center, Davis, CA 95616, USA"}]},{"given":"Nikolas","family":"Ortman","sequence":"additional","affiliation":[{"name":"Los Angeles District, US Army Corps of Engineers, Los Angeles, CA 90017, USA"},{"name":"Morrison-Maierle, Missoula, MT 59801, USA"}]},{"given":"Renato","family":"Amorim","sequence":"additional","affiliation":[{"name":"Departamento Nacional de Infraestrutura de Transportes, Brasilia 70040-902, Brazil"},{"name":"Department of Civil and Environmental Engineering, University of Iowa, Iowa, IA 52242, USA"}]},{"given":"Ian","family":"Floyd","sequence":"additional","affiliation":[{"name":"Coastal and Hydraulics Laboratory, US Army Corps of Engineers Engineering Research and Development Center, Vicksburg, MS 39180, USA"}]},{"given":"Moosub","family":"Eom","sequence":"additional","affiliation":[{"name":"Los Angeles District, US Army Corps of Engineers, Los Angeles, CA 90017, USA"}]},{"given":"Calvin","family":"Creech","sequence":"additional","affiliation":[{"name":"Mobile District, US Army Corps of Engineers, Mobile, AL 36602, USA"}]},{"given":"Alejandro","family":"S\u00e1nchez","sequence":"additional","affiliation":[{"name":"Hydrologic Engineering Center, Davis, CA 95616, USA"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1140","DOI":"10.1130\/GES02048.1","article-title":"Inundation, flow dynamics, and damage in the 9 January 2018 Montecito debris-flow event, California, USA: Opportunities and challenges for post-wildfire risk assessment","volume":"15","author":"Kean","year":"2019","journal-title":"Geosphere"},{"key":"ref_2","unstructured":"Robert, D., and Niehaus, I. 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